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Printed, Flexible and Rechargeable Battery Can Power Wearable Sensors

Nanoengineers at the University of California San Diego have developed the first printed battery that is flexible, stretchable and rechargeable. The zinc batteries could be used to power everything from wearable sensors to solar cells and other kinds of electronics. The work appears in the April 19, 2017 issue of Advanced Energy Materials.

Neutrons Provide the First Nanoscale Look at a Living Cell Membrane

A research team from the Department of Energy's Oak Ridge National Laboratory has performed the first-ever direct nanoscale examination of a living cell membrane. In doing so, it also resolved a long-standing debate by identifying tiny groupings of lipid molecules that are likely key to the cell's functioning.

How X-Rays Helped to Solve Mystery of Floating Rocks

Experiments at Berkeley Lab's Advanced Light Source have helped scientists to solve a mystery of why some rocks can float for years in the ocean, traveling thousands of miles before sinking.

Special X-Ray Technique Allows Scientists to See 3-D Deformations

In a new study published last Friday in Science, researchers at Argonne used an X-ray scattering technique called Bragg coherent diffraction imaging to reconstruct in 3-D the size and shape of grain defects. These defects create imperfections in the lattice of atoms inside a grain that can give rise to interesting material properties and effects.

Neptune: Neutralizer-Free Plasma Propulsion

The most established plasma propulsion concepts are gridded-ion thrusters that accelerate and emit a larger number of positively charged particles than those that are negatively charged. To enable the spacecraft to remain charge-neutral, a "neutralizer" is used to inject electrons to exactly balance the positive ion charge in the exhaust beam. However, the neutralizer requires additional power from the spacecraft and increases the size and weight of the propulsion system. Researchers are investigating how the radio-frequency self-bias effect can be used to remove the neutralizer altogether, and they report their work in this week's Physics of Plasmas.

Report Sheds New Insights on the Spin Dynamics of a Material Candidate for Low-Power Devices

In a report published in Nano LettersArgonne researchers reveal new insights into the properties of a magnetic insulator that is a candidate for low-power device applications; their insights form early stepping-stones towards developing high-speed, low-power electronics that use electron spin rather than charge to carry information.

Researchers Find Computer Code That Volkswagen Used to Cheat Emissions Tests

An international team of researchers has uncovered the mechanism that allowed Volkswagen to circumvent U.S. and European emission tests over at least six years before the Environmental Protection Agency put the company on notice in 2015 for violating the Clean Air Act. During a year-long investigation, researchers found code that allowed a car's onboard computer to determine that the vehicle was undergoing an emissions test.

Physicists Discover That Lithium Oxide on Tokamak Walls Can Improve Plasma Performance

A team of physicists has found that a coating of lithium oxide on the inside of fusion machines known as tokamaks can absorb as much deuterium as pure lithium can.

Scientists Perform First Basic Physics Simulation of Spontaneous Transition of the Edge of Fusion Plasma to Crucial High-Confinement Mode

PPPL physicists have simulated the spontaneous transition of turbulence at the edge of a fusion plasma to the high-confinement mode that sustains fusion reactions. The research was achieved with the extreme-scale plasma turbulence code XGC developed at PPPL in collaboration with a nationwide team.

Green Fleet Technology

New research at Penn State addresses the impact delivery trucks have on the environment by providing green solutions that keep costs down without sacrificing efficiency.


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Rensselaer Polytechnic Institute Graduates Urged to Embrace Change at 211th Commencement

Describing the dizzying pace of technological innovation, former United States Secretary of Energy Ernest J. Moniz urged graduates to "anticipate career change, welcome it, and manage it to your and your society's benefit" at the 211th Commencement at Rensselaer Polytechnic Institute (RPI) Saturday.

ORNL Welcomes Innovation Crossroads Entrepreneurial Research Fellows

Oak Ridge National Laboratory today welcomed the first cohort of innovators to join Innovation Crossroads, the Southeast region's first entrepreneurial research and development program based at a U.S. Department of Energy national laboratory.

Department of Energy Secretary Recognizes Argonne Scientists' Work to Fight Ebola, Cancer

Two groups of researchers at Argonne earned special awards from the office of the U.S. Secretary of Energy for addressing the global health challenges of Ebola and cancer.

Jefferson Science Associates, LLC Recognized for Leadership in Small Business Utilization

Jefferson Lab/Jefferson Science Associates has a long-standing commitment to doing business with and mentoring small businesses. That commitment and support received national recognition at the 16th Annual Dept. of Energy Small Business Forum and Expo held May 16-18, 2017 in Kansas City, Mo.

Rensselaer Polytechnic Institute President's Commencement Colloquy to Address "Criticality, Incisiveness, Creativity"

To kick off the Rensselaer Polytechnic Institute Commencement weekend, the annual President's Commencement Colloquy will take place on Friday, May 19, beginning at 3:30 p.m. The discussion, titled "Criticality, Incisiveness, Creativity," will include the Honorable Ernest J. Moniz, former Secretary of Energy, and the Honorable Roger W. Ferguson Jr., President and CEO of TIAA, and will be moderated by Rensselaer President Shirley Ann Jackson.

ORNL, University of Tennessee Launch New Doctoral Program in Data Science

The Tennessee Higher Education Commission has approved a new doctoral program in data science and engineering as part of the Bredesen Center for Interdisciplinary Research and Graduate Education.

SurfTec Receives $1.2 Million Energy Award to Develop Novel Coating

The Department of Energy has awarded $1.2 million to SurfTec LLC, a company affiliated with the U of A Technology Development Foundation, to continue developing a nanoparticle-based coating to replace lead-based journal bearings in the next generation of electric machines.

Ames Laboratory Scientist Inducted Into National Inventors Hall of Fame

Iver Anderson, senior metallurgist at Ames Laboratory, has been inducted into the National Inventors Hall of Fame.

DOE HPC4Mfg Program Funds 13 New Projects to Improve U.S. Energy Technologies Through High Performance Computing

A U.S. Department of Energy (DOE) program designed to spur the use of high performance supercomputers to advance U.S. manufacturing is funding 13 new industry projects for a total of $3.9 million.

Penn State Wind Energy Club Breezes to Victory in Collegiate Wind Competition

The Penn State Wind Energy Club breezed through the field at the U.S. Department of Energy Collegiate Wind Competition 2017 Technical Challenge, held April 20-22 at the National Wind Technology Center near Boulder, Colorado--earning its third overall victory in four years at the Collegiate Wind Competition.


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Casting a Wide Net

Designed molecules will provide positive impacts in energy production by selectively removing unwanted ions from complex solutions.

New Software Tools Streamline DNA Sequence Design-and-Build Process

Enhanced software tools will accelerate gene discovery and characterization, vital for new forms of fuel production.

The Ultrafast Interplay Between Molecules and Materials

Computer calculations by the Center for Solar Fuels, an Energy Frontier Research Center, shed light on nebulous interactions in semiconductors relevant to dye-sensitized solar cells.

Supercapacitors: WOODn't That Be Nice

Researchers at Nanostructures for Electrical Energy Storage, an Energy Frontier Research Center, take advantage of nature-made materials and structure for energy storage research.

Groundwater Flow Is Key for Modeling the Global Water Cycle

Water table depth and groundwater flow are vital to understanding the amount of water that plants transmit to the atmosphere.

Finding the Correct Path

A new computational technique greatly simplifies the complex reaction networks common to catalysis and combustion fields.

Opening Efficient Routes to Everyday Plastics

A new material from the Inorganometallic Catalyst Design Center, an Energy Frontier Research Center, facilitates the production of key industrial supplies.

Fight to the Top: Silver and Gold Compete for the Surface of a Bimetallic Solid

It's the classic plot of a buddy movie. Two struggling bodies team up to drive the plot and do good together. That same idea, when it comes to metals, could help scientists solve a big problem: the amount of energy consumed by making chemicals.

Saving Energy Through Light Control

New materials, designed by researchers at the Center for Excitonics, an Energy Frontier Research Center, can reduce energy consumption with the flip of a switch.

Teaching Perovskites to Swim

Scientists at the ANSER Energy Frontier Research Center designed a two-component layer protects a sunlight-harvesting device from water and heat.


Researchers Develop a New Catalyst for Water Splitting

Article ID: 674067

Released: 2017-05-03 12:05:38

Source Newsroom: SLAC National Accelerator Laboratory

  • Credit: Andy Freeberg/SLAC National Accelerator Laboratory

    Scientists have developed a new molybdenum-coated catalyst that prevents an unwanted back reaction in certain chemical systems that split water into hydrogen and oxygen.

  • Credit: SLAC National Accelerator Laboratory

    Graph of the photocatalytic water splitting performance of a 0.3 wt% Pt/SrTiO3 catalyst with and without Mo coating under UV-light irradiation. The Mo-coated catalyst generated increasing amounts of hydrogen gas for 24 hours with the light on, and inhibited water reformation when the light was off. Whereas, the uncoated catalyst increased hydrogen production for only six hours with the light on and the level decreased when the light was off due to water formation. Oxygen production followed a similar pattern but at half the amount of hydrogen, since water has two hydrogen atoms for each oxygen atom.

Hydrogen is one of the most promising clean fuels for use in cars, houses and portable generators. When produced from water using renewable energy resources, it is also a sustainable fuel with no carbon footprint.

However, water-splitting systems require a very efficient catalyst to speed up the chemical reaction that splits water into hydrogen and oxygen, while preventing the gases from recombining back into water. Now an international research team, including scientists at the Department of Energy’s SLAC National Accelerator Laboratory, has developed a new catalyst with a molybdenum coating that prevents this problematic back reaction and works well in realistic operating conditions.

A key part of the development centered on understanding how the molybdenum coating worked using experiments at SLAC’s Stanford Synchrotron Radiation Lightsource (SSRL), a DOE Office of Science User Facility. The scientists reported their results April 13 in Angewandte Chemie.

“When you split water into hydrogen and oxygen, the gaseous products of the reaction are easily recombined back to water and it’s crucial to avoid this,” said Angel Garcia-Esparza, lead author and currently a postdoctoral researcher from the Ecole Normale Supérieure de Lyon. “We discovered that a molybdenum-coated catalyst is capable of selectively producing hydrogen from water while inhibiting the back reactions of water formation.”

The experiments demonstrated that their molybdenum coating strategy has applications in electrocatalysis and photocatalysis devices, added Garcia-Esparza. These are devices that help drive forward a reaction using electricity or light.

Searching for Stability

Garcia-Esparza helped develop the new catalyst as a graduate student at King Abdullah University of Science and Technology (KAUST) in Saudi Arabia under the direction of Kazuhiro Takanabe, an associate professor of chemical science at KAUST. Takanabe’s research group explored the stability, performance and function of many different elements before selecting molybdenum as the coating for a standard platinum-based catalyst.

“Finding a coating that worked well in the acid electrolyte used for water splitting was a major challenge for my collaborators, because many materials quickly degrade in the acidic conditions,” said co-author Dimosthenis Sokaras, a staff scientist at SLAC.

Of the coatings they tested, “Molybdenum was the best-performing material in acidic media, where the conditions for hydrogen evolution are favorable and facile,” Garcia-Esparza explained.

Testing the Performance

Another major challenge was finding a way to measure the properties of their molybdenum-coated catalyst, because these molybdenum compounds are not stable when exposed to air. “Taking the catalyst out of water perturbs the identity of the material,” said Garcia-Esparza. “Therefore, it was necessary to study the electrocatalyst under working conditions, which is difficult.”

So Garcia-Esparza spent a summer performing electrochemistry experiments at SSRL to characterize the new catalyst under operational conditions. “The idea was to work together to see how the molybdenum-coated catalyst performed and determine its electronic structure when it was operating,” said Sokaras. “We wanted to understand why the back reaction doesn’t happen.”

They tested a bare platinum catalyst, with and without a molybdenum coating, during water electrolysis at SSRL, using in operando X-ray absorption spectroscopy with a custom-made electrochemical cell. “At SSRL, we were essentially able to do electrochemistry while analyzing the sample with synchrotron radiation,” Garcia-Esparza said. “The experiments performed at SLAC were the final piece of the puzzle to determine the local structure and state of the electrocatalyst under the operational conditions of hydrogen production.”

 “Our findings support that the molybdenum layer acts as a membrane to block the oxygen and hydrogen gases from reaching near the platinum surface, which prevents water formation,” Sokaras said.

In addition, the research team explored photocatalysis applications. They built a photocatalytic water-splitting system using either a standard catalyst of platinum on strontium titanium oxide (Pt/SrTiO3) or the same catalyst coated with molybdenum. Both systems were tested at KAUST with the lights on and off — that is, with and without an energy source driving the water-splitting reaction.

When the light was on, the standard Pt/SrTiO3 catalyst increased hydrogen production for only six hours because the system lost efficiency due to the back reaction. When the lights were then turned off, the amount of hydrogen decreased with time — verifying that significant amounts of the gases were recombining to form water.

In contrast, the molybdenum-coated catalyst continuously split water to generate increasing amounts of hydrogen gas for 24 hours, producing about twice as much hydrogen gas as the standard catalyst in one day. In addition, the amount of hydrogen remained stable in the dark, confirming that the coating inhibited water formation

These results are promising, but more work still needs to be done before the catalyst can be used in a practical device. Sokaras said, “I think we’re far from actually talking about a commercial device, but it is certainly a huge improvement to have this new catalyst material that prevents the back reaction. Now we need to find a way to make the coating more stable so it produces hydrogen for even longer.”

The research team included scientists from SSRL, King Abdullah University of Science and Technology, Fukuoka University, University of Tokyo, and the Center for High Pressure Science and Technology Advanced Research in Shanghai, China. The work was supported by King Abdullah University of Science and Technology. 


SLAC is a multi-program laboratory exploring frontier questions in photon science, astrophysics, particle physics and accelerator research. Located in Menlo Park, Calif., SLAC is operated by Stanford University for the U.S. Department of Energy's Office of Science. For more information, please visit slac.stanford.edu.

SLAC National Accelerator Laboratory is supported by the Office of Science of the U.S. Department of Energy. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.